The Sun

The Sun, together with its planetary system, which includes Earth, is known as the solar system. The sun is at the center of the solar system.

It is composed of 70 percent hydrogen, 28 percent helium and two percent various metals.


Mini-test: THE SUN 

Question 1: The sun is a medium-sized star. But it’s pretty enormous compared to Earth. How many Earths could fit inside the sun?
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Question 2: Nuclear fusion in the sun’s core converts
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B.  
C.  
D.  

 

The next lesson: Types of Stars, both lessons are included in Practice Tests.

The following transcript is provided for your convenience.
Its diameter is 1,390,000 km and to give you some perspective, that’s about 109 times earth’s diameter. Because it is such a large star and it is the closest one to us, we are able to see it and we do benefit from some of its effects.

The sun is one of about 100 billion stars in the Milky Way Galaxy and stars are basically balls of burning gas. Hydrogen and helium being the primary gases of the sun, so since it’s a ball of burning gas, it’s going to have some high temperatures.

The sun surface temperature is around 5800 Kelvin and the core temperature reaches 15,600,000 K.
The surface of the sun is called the photosphere, so that would be like its outer most layer, the photosphere.
Then beyond the photosphere which is the surface of the sun, we have the chromosphere.

Next we have the corona, the corona extends millions of miles into space, after the chromospheres.
Then you’ve got sun spots which are relatively cool regions on the surface of the sun, with temperatures around 3800 K.
Finally, the heliosphere Think of the heliosphere like a bubble surrounding the sun with the sun near its center.

The next lesson: Types of Stars, both lessons are included in Practice Tests.

the-sun